Most often in May, 29 days.
Highest follower count seen that year: 29,837.
January
Jan 1 13:00–15:00, 23:00–24:00 Jan 2 00:00–01:00, 23:00–24:00 Jan 3 00:00–03:00 Jan 4 12:00–15:00 Jan 5 13:00–15:00 Jan 7 00:00–02:00, 13:00–15:00 Jan 14 13:00–15:00 Jan 18 12:00–14:00 Jan 19 12:00–15:00 Jan 21 12:00–15:00 Jan 22 13:00–14:00, 23:00–24:00 Jan 23 00:00–02:00 Jan 24 23:00–24:00 Jan 25 13:00–15:00 Jan 26 12:00–15:00 Jan 27 00:00–02:00, 22:00–24:00 Jan 28 00:00–02:00, 13:00–14:00 Jan 29 13:00–15:00, 23:00–24:00 Jan 30 00:00–02:00 Jan 31 23:00–24:00
February
Feb 1 00:00–03:00 Feb 2 00:00–03:00, 12:00–15:00, 23:00–24:00 Feb 3 00:00–02:00 Feb 4 12:00–15:00 Feb 5 00:00–03:00 Feb 6 00:00–02:00 Feb 9 12:00–15:00, 23:00–24:00 Feb 10 00:00–02:00 Feb 11 12:00–14:00, 23:00–24:00 Feb 12 00:00–02:00, 22:00–24:00 Feb 13 00:00–02:00, 13:00–15:00, 23:00–24:00 Feb 14 00:00–02:00, 23:00–24:00 Feb 15 00:00–03:00, 22:00–24:00 Feb 16 00:00–01:00, 13:00–15:00, 22:00–24:00 Feb 17 00:00–02:00 Feb 18 11:00–14:00, 22:00–24:00 Feb 19 00:00–02:00 Feb 20 13:00–14:00, 23:00–24:00 Feb 21 00:00–02:00, 13:00–15:00, 23:00–24:00 Feb 22 00:00–02:00, 13:00–16:00, 23:00–24:00 Feb 23 00:00–02:00, 12:00–16:00 Feb 27 12:00–15:00, 23:00–24:00 Feb 28 00:00–01:00, 13:00–15:00, 23:00–24:00
March
Mar 1 00:00–02:00, 12:00–16:00, 23:00–24:00 Mar 2 00:00–02:00, 12:00–15:00, 23:00–24:00 Mar 3 00:00–02:00 Mar 4 12:00–14:00 Mar 6 13:00–15:00, 23:00–24:00 Mar 7 00:00–02:00, 23:00–24:00 Mar 8 00:00–02:00, 13:00–15:00 Mar 9 00:00–02:00, 12:00–15:00, 23:00–24:00 Mar 10 00:00–01:00 Mar 11 12:00–14:00, 23:00–24:00 Mar 12 00:00–02:00 Mar 13 23:00–24:00 Mar 14 00:00–01:00, 13:00–14:00, 23:00–24:00 Mar 15 00:00–02:00, 12:00–14:00, 23:00–24:00 Mar 16 00:00–02:00, 12:00–16:00, 23:00–24:00 Mar 18 12:00–14:00, 23:00–24:00 Mar 19 00:00–02:00 Mar 20 23:00–24:00 Mar 21 00:00–02:00, 13:00–15:00, 23:00–24:00 Mar 22 00:00–01:00 Mar 23 12:00–15:00 Mar 25 12:00–15:00, 23:00–24:00 Mar 26 00:00–01:00 Mar 27 23:00–24:00 Mar 28 00:00–02:00, 13:00–15:00 Mar 31 23:00–24:00
April
Apr 1 00:00–01:00, 11:00–13:00, 23:00–24:00 Apr 3 23:00–24:00 Apr 4 00:00–01:00, 12:00–13:00, 23:00–24:00 Apr 5 11:00–13:00 Apr 6 00:00–01:00, 11:00–14:00 Apr 7 00:00–01:00, 23:00–24:00 Apr 8 00:00–01:00, 11:00–13:00 Apr 10 12:00–14:00, 22:00–24:00 Apr 11 00:00–01:00, 12:00–14:00, 22:00–24:00 Apr 12 00:00–02:00, 12:00–13:00, 23:00–24:00 Apr 13 00:00–02:00, 11:00–14:00, 23:00–24:00 Apr 14 00:00–01:00 Apr 15 11:00–12:00, 22:00–24:00 Apr 16 00:00–01:00 Apr 17 22:00–24:00 Apr 20 11:00–14:00 Apr 22 11:00–13:00 Apr 24 22:00–24:00 Apr 25 00:00–01:00, 11:00–13:00, 22:00–24:00 Apr 26 00:00–01:00, 12:00–15:00, 23:00–24:00 Apr 27 00:00–01:00, 11:00–14:00 Apr 28 23:00–24:00 Apr 29 00:00–01:00, 11:00–12:00
May
May 1 11:00–13:00 May 2 00:00–01:00, 11:00–14:00, 22:00–24:00 May 3 00:00–01:00, 23:00–24:00 May 4 00:00–01:00, 11:00–14:00 May 5 00:00–02:00 May 6 11:00–13:00, 22:00–24:00 May 7 00:00–01:00 May 8 22:00–24:00 May 9 00:00–01:00, 12:00–14:00, 23:00–24:00 May 10 00:00–01:00, 12:00–14:00, 22:00–24:00 May 11 00:00–02:00, 11:00–14:00, 22:00–24:00 May 12 00:00–01:00 May 13 11:00–12:00, 22:00–24:00 May 14 00:00–01:00 May 15 22:00–24:00 May 16 00:00–01:00, 22:00–24:00 May 17 00:00–01:00, 12:00–15:00 May 18 11:00–14:00, 23:00–24:00 May 19 00:00–02:00 May 20 11:00–13:00, 23:00–24:00 May 21 00:00–02:00 May 24 12:00–14:00 May 25 12:00–13:00, 23:00–24:00 May 26 00:00–01:00 May 27 11:00–13:00, 22:00–24:00 May 28 00:00–01:00 May 29 22:00–24:00 May 30 00:00–02:00, 22:00–24:00 May 31 00:00–02:00, 11:00–14:00, 23:00–24:00
June
Jun 1 00:00–02:00, 11:00–13:00, 23:00–24:00 Jun 2 00:00–02:00 Jun 3 11:00–13:00, 23:00–24:00 Jun 4 00:00–02:00 Jun 5 22:00–24:00 Jun 6 00:00–01:00, 23:00–24:00 Jun 7 00:00–02:00 Jun 8 11:00–14:00, 23:00–24:00 Jun 9 00:00–01:00 Jun 10 10:00–13:00 Jun 11 12:00–14:00 Jun 12 23:00–24:00 Jun 13 00:00–01:00 Jun 14 12:00–14:00 Jun 15 00:00–02:00, 11:00–14:00, 23:00–24:00 Jun 16 00:00–02:00 Jun 17 11:00–13:00, 22:00–24:00 Jun 18 00:00–03:00 Jun 19 23:00–24:00 Jun 20 00:00–01:00, 23:00–24:00 Jun 21 00:00–02:00, 12:00–14:00 Jun 22 11:00–14:00, 23:00–24:00 Jun 23 00:00–02:00 Jun 24 11:00–13:00, 22:00–24:00 Jun 25 00:00–02:00 Jun 30 22:00–24:00
July
Jul 1 00:00–01:00, 10:00–13:00, 23:00–24:00 Jul 2 00:00–02:00 Jul 3 22:00–24:00 Jul 4 00:00–01:00 Jul 5 12:00–14:00, 22:00–24:00 Jul 6 00:00–01:00, 11:00–14:00 Jul 7 22:00–24:00 Jul 8 00:00–01:00, 10:00–13:00, 22:00–24:00 Jul 9 00:00–03:00 Jul 11 22:00–24:00 Jul 12 00:00–01:00, 23:00–24:00 Jul 13 00:00–02:00, 11:00–13:00 Jul 15 23:00–24:00 Jul 16 00:00–02:00, 23:00–24:00 Jul 17 00:00–02:00 Jul 18 23:00–24:00 Jul 19 00:00–01:00 Jul 20 12:00–14:00, 23:00–24:00 Jul 21 00:00–02:00 Jul 22 11:00–13:00 Jul 23 00:00–03:00 Jul 24 23:00–24:00 Jul 25 00:00–01:00 Jul 26 11:00–14:00 Jul 27 23:00–24:00 Jul 28 00:00–02:00 Jul 29 11:00–13:00
August
Aug 1 23:00–24:00 Aug 2 00:00–02:00, 12:00–13:00 Aug 3 12:00–14:00, 23:00–24:00 Aug 4 00:00–02:00 Aug 5 23:00–24:00 Aug 6 00:00–02:00 Aug 7 23:00–24:00 Aug 8 00:00–02:00 Aug 9 12:00–13:00 Aug 10 00:00–02:00, 12:00–14:00 Aug 13 23:00–24:00 Aug 14 00:00–02:00, 23:00–24:00 Aug 15 00:00–02:00 Aug 16 23:00–24:00 Aug 17 00:00–02:00, 12:00–14:00, 23:00–24:00 Aug 18 00:00–02:00, 23:00–24:00 Aug 19 00:00–03:00 Aug 26 10:00–12:00 Aug 27 00:00–02:00 Aug 28 22:00–24:00 Aug 29 00:00–01:00, 23:00–24:00 Aug 30 00:00–02:00, 12:00–13:00, 23:00–24:00 Aug 31 00:00–02:00, 23:00–24:00
September
Sep 1 00:00–03:00 Sep 2 11:00–13:00, 23:00–24:00 Sep 3 00:00–04:00, 23:00–24:00 Sep 4 00:00–02:00 Sep 5 00:00–01:00, 23:00–24:00 Sep 6 00:00–03:00, 12:00–13:00, 23:00–24:00 Sep 7 00:00–01:00, 12:00–14:00, 23:00–24:00 Sep 8 00:00–02:00 Sep 9 23:00–24:00 Sep 10 00:00–03:00, 23:00–24:00 Sep 11 00:00–02:00 Sep 14 22:00–24:00 Sep 15 00:00–02:00 Sep 16 10:00–13:00 Sep 17 23:00–24:00 Sep 18 00:00–03:00 Sep 19 23:00–24:00 Sep 20 00:00–03:00, 12:00–14:00, 23:00–24:00 Sep 21 00:00–01:00, 12:00–14:00, 23:00–24:00 Sep 22 00:00–03:00 Sep 23 11:00–13:00, 23:00–24:00 Sep 24 00:00–03:00, 23:00–24:00 Sep 25 00:00–03:00 Sep 26 23:00–24:00 Sep 27 00:00–02:00 Sep 28 22:00–24:00 Sep 29 00:00–02:00 Sep 30 10:00–13:00
October
Oct 1 00:00–03:00 Oct 2 23:00–24:00 Oct 3 00:00–02:00 Oct 4 00:00–02:00 Oct 5 12:00–14:00, 23:00–24:00 Oct 6 00:00–03:00 Oct 7 10:00–12:00, 23:00–24:00 Oct 8 00:00–01:00 Oct 9 23:00–24:00 Oct 10 00:00–02:00, 23:00–24:00 Oct 11 00:00–02:00, 23:00–24:00 Oct 12 00:00–02:00, 11:00–15:00 Oct 14 11:00–13:00, 23:00–24:00 Oct 15 00:00–03:00 Oct 16 00:00–03:00 Oct 17 23:00–24:00 Oct 18 00:00–02:00 Oct 19 11:00–14:00, 23:00–24:00 Oct 20 00:00–02:00 Oct 21 11:00–12:00, 23:00–24:00 Oct 22 00:00–02:00 Oct 28 12:00–13:00 Oct 29 00:00–03:00 Oct 31 00:00–02:00
November
Nov 3 00:00–02:00 Nov 4 12:00–14:00 Nov 5 00:00–03:00 Nov 9 00:00–04:00 Nov 10 00:00–03:00 Nov 12 00:00–04:00 Nov 14 00:00–03:00 Nov 16 12:00–15:00 Nov 17 00:00–03:00 Nov 18 12:00–13:00 Nov 19 00:00–04:00 Nov 23 12:00–15:00 Nov 24 00:00–04:00 Nov 26 00:00–04:00 Nov 29 00:00–02:00 Nov 30 13:00–15:00
December
Dec 1 00:00–03:00 Dec 3 00:00–03:00 Dec 5 01:00–03:00 Dec 10 00:00–03:00 Dec 14 13:00–15:00 Dec 15 00:00–04:00 Dec 17 00:00–02:00 Dec 19 00:00–02:00 Dec 21 12:00–15:00 Dec 22 00:00–03:00 Dec 24 00:00–04:00 Dec 29 00:00–04:00 Dec 30 13:00–15:00 Dec 31 00:00–03:00