Most often in May, 30 days.
Highest follower count seen that year: 5,724.
January
Jan 8 22:00–24:00 Jan 9 00:00–03:00, 21:00–24:00 Jan 10 00:00–03:00 Jan 12 21:00–24:00 Jan 13 00:00–03:00, 21:00–24:00 Jan 14 00:00–03:00, 21:00–24:00 Jan 15 00:00–03:00, 21:00–24:00 Jan 16 00:00–03:00, 21:00–24:00 Jan 17 00:00–03:00, 14:00–19:00 Jan 21 21:00–24:00 Jan 22 01:00–02:00, 21:00–24:00 Jan 23 00:00–03:00, 21:00–22:00 Jan 24 02:00–03:00, 16:00–21:00 Jan 27 17:00–21:00 Jan 28 21:00–24:00 Jan 29 00:00–03:00, 21:00–24:00 Jan 30 00:00–03:00, 21:00–24:00 Jan 31 00:00–03:00, 14:00–20:00
February
Feb 3 21:00–24:00 Feb 4 00:00–02:00, 14:00–21:00 Feb 5 15:00–21:00 Feb 7 21:00–24:00 Feb 8 00:00–03:00, 21:00–24:00 Feb 9 00:00–03:00 Feb 10 14:00–20:00 Feb 11 21:00–24:00 Feb 12 00:00–03:00, 20:00–24:00 Feb 13 00:00–03:00, 21:00–24:00 Feb 14 00:00–03:00, 21:00–24:00 Feb 15 00:00–02:00 Feb 18 21:00–24:00 Feb 19 00:00–03:00, 21:00–24:00 Feb 20 00:00–03:00, 21:00–24:00 Feb 21 00:00–03:00 Feb 23 21:00–23:00 Feb 24 00:00–03:00, 15:00–21:00 Feb 25 21:00–23:00 Feb 26 00:00–03:00, 22:00–24:00 Feb 27 00:00–03:00, 21:00–23:00 Feb 28 00:00–03:00, 15:00–19:00
April
Apr 23 21:00–24:00 Apr 24 00:00–02:00, 15:00–18:00 Apr 25 14:00–24:00 Apr 26 00:00–01:00, 18:00–24:00 Apr 27 00:00–02:00, 22:00–24:00 Apr 28 00:00–01:00, 19:00–24:00 Apr 29 00:00–02:00, 19:00–24:00 Apr 30 01:00–02:00, 19:00–24:00
May
May 1 00:00–02:00, 20:00–24:00 May 2 00:00–02:00, 20:00–23:00 May 3 20:00–24:00 May 4 19:00–23:00 May 5 18:00–23:00 May 6 19:00–24:00 May 7 00:00–03:00, 18:00–24:00 May 8 00:00–02:00, 19:00–24:00 May 9 00:00–02:00, 21:00–24:00 May 10 20:00–23:00 May 11 21:00–23:00 May 12 00:00–01:00, 17:00–24:00 May 13 00:00–02:00, 15:00–24:00 May 14 17:00–21:00 May 15 01:00–02:00, 20:00–23:00 May 16 00:00–02:00, 19:00–24:00 May 17 00:00–02:00, 18:00–24:00 May 18 00:00–02:00, 19:00–24:00 May 19 13:00–21:00 May 21 20:00–24:00 May 22 00:00–02:00, 20:00–24:00 May 23 00:00–02:00, 18:00–24:00 May 24 00:00–02:00, 18:00–24:00 May 25 00:00–02:00, 19:00–24:00 May 26 18:00–24:00 May 27 00:00–02:00, 19:00–24:00 May 28 13:00–20:00 May 29 18:00–24:00 May 30 00:00–02:00, 21:00–23:00 May 31 01:00–03:00, 18:00–23:00
June
Jun 2 19:00–24:00 Jun 3 00:00–02:00, 20:00–24:00 Jun 4 00:00–02:00, 20:00–23:00 Jun 5 00:00–02:00, 20:00–24:00 Jun 6 00:00–02:00 Jun 7 18:00–23:00 Jun 8 20:00–24:00 Jun 9 00:00–02:00, 20:00–24:00 Jun 10 00:00–02:00, 20:00–24:00 Jun 11 00:00–02:00, 19:00–24:00 Jun 12 00:00–01:00, 13:00–18:00, 20:00–24:00 Jun 13 00:00–01:00 Jun 15 21:00–22:00 Jun 16 20:00–24:00 Jun 17 00:00–02:00, 20:00–24:00 Jun 18 20:00–24:00 Jun 19 00:00–02:00, 20:00–24:00 Jun 20 00:00–01:00, 20:00–24:00 Jun 21 19:00–24:00 Jun 22 20:00–24:00 Jun 23 00:00–02:00, 19:00–24:00 Jun 24 00:00–02:00, 19:00–24:00 Jun 25 20:00–24:00 Jun 26 00:00–02:00 Jun 27 20:00–24:00 Jun 28 00:00–01:00, 19:00–24:00 Jun 29 00:00–02:00, 20:00–24:00 Jun 30 00:00–02:00, 13:00–21:00
July
Jul 2 20:00–24:00 Jul 3 00:00–02:00, 21:00–24:00 Jul 4 00:00–02:00, 20:00–23:00 Jul 5 00:00–02:00, 20:00–23:00 Jul 6 20:00–21:00, 23:00–24:00 Jul 7 20:00–24:00 Jul 8 00:00–02:00, 21:00–24:00 Jul 9 00:00–02:00, 20:00–24:00 Jul 10 00:00–02:00, 20:00–24:00 Jul 11 00:00–02:00, 19:00–24:00 Jul 13 20:00–24:00 Jul 14 00:00–02:00, 20:00–24:00 Jul 15 01:00–02:00 Jul 16 21:00–24:00 Jul 17 20:00–24:00 Jul 18 00:00–01:00, 20:00–23:00 Jul 19 21:00–23:00 Jul 20 19:00–24:00 Jul 21 00:00–02:00, 20:00–24:00 Jul 22 00:00–02:00, 20:00–23:00 Jul 24 20:00–24:00 Jul 25 00:00–01:00, 20:00–24:00 Jul 26 00:00–02:00, 20:00–23:00 Jul 27 00:00–02:00, 20:00–24:00 Jul 28 00:00–01:00, 20:00–24:00 Jul 29 00:00–02:00, 20:00–24:00 Jul 30 01:00–02:00, 18:00–24:00 Jul 31 00:00–02:00, 14:00–21:00
August
Aug 1 20:00–24:00 Aug 3 19:00–24:00 Aug 4 00:00–02:00, 16:00–23:00 Aug 6 16:00–23:00 Aug 7 16:00–24:00 Aug 8 18:00–24:00 Aug 9 00:00–01:00, 20:00–24:00 Aug 10 00:00–01:00, 20:00–24:00 Aug 11 00:00–02:00, 20:00–24:00 Aug 12 00:00–02:00, 19:00–24:00 Aug 13 00:00–01:00, 17:00–23:00 Aug 14 19:00–24:00 Aug 15 00:00–01:00 Aug 16 20:00–24:00 Aug 17 00:00–03:00, 19:00–24:00 Aug 18 00:00–01:00, 19:00–24:00 Aug 19 00:00–01:00, 19:00–24:00 Aug 20 00:00–01:00, 19:00–24:00 Aug 21 00:00–01:00, 19:00–24:00 Aug 22 19:00–24:00 Aug 23 20:00–23:00 Aug 25 18:00–24:00 Aug 26 19:00–24:00 Aug 27 00:00–01:00, 17:00–23:00 Aug 28 19:00–24:00 Aug 29 18:00–24:00 Aug 30 20:00–24:00 Aug 31 00:00–01:00
September
Sep 1 19:00–24:00 Sep 2 00:00–01:00, 19:00–24:00 Sep 3 00:00–01:00, 19:00–24:00 Sep 4 00:00–01:00, 19:00–24:00 Sep 5 00:00–01:00, 20:00–24:00 Sep 6 00:00–02:00 Sep 8 20:00–24:00 Sep 9 00:00–01:00, 19:00–23:00 Sep 10 19:00–23:00 Sep 11 13:00–18:00 Sep 13 21:00–23:00 Sep 15 19:00–24:00 Sep 16 00:00–01:00, 19:00–24:00 Sep 17 00:00–01:00, 19:00–24:00 Sep 18 00:00–01:00, 19:00–24:00 Sep 19 00:00–01:00, 19:00–24:00 Sep 20 00:00–01:00 Sep 22 19:00–24:00 Sep 23 00:00–01:00, 13:00–19:00 Sep 24 19:00–24:00 Sep 25 00:00–01:00, 19:00–24:00 Sep 26 18:00–23:00 Sep 27 21:00–23:00 Sep 29 19:00–24:00 Sep 30 00:00–01:00, 21:00–24:00
October
Oct 1 00:00–01:00, 15:00–16:00, 18:00–20:00 Oct 2 19:00–24:00 Oct 3 00:00–01:00 Oct 5 19:00–24:00 Oct 6 00:00–01:00, 21:00–24:00 Oct 7 00:00–01:00, 15:00–20:00 Oct 8 19:00–24:00 Oct 9 20:00–24:00 Oct 10 00:00–01:00 Oct 12 19:00–23:00 Oct 13 00:00–01:00, 20:00–24:00 Oct 14 00:00–01:00, 15:00–20:00 Oct 15 19:00–23:00 Oct 16 00:00–01:00, 19:00–24:00 Oct 17 00:00–01:00 Oct 19 19:00–23:00 Oct 20 19:00–24:00 Oct 21 19:00–24:00 Oct 22 00:00–02:00, 15:00–20:00 Oct 23 20:00–24:00 Oct 24 00:00–01:00, 20:00–23:00 Oct 26 20:00–23:00 Oct 27 15:00–21:00 Oct 29 00:00–02:00 Oct 30 21:00–24:00 Oct 31 00:00–03:00, 16:00–20:00
November
Nov 2 21:00–24:00 Nov 3 00:00–02:00, 15:00–21:00 Nov 4 20:00–24:00 Nov 5 00:00–02:00, 20:00–24:00 Nov 6 01:00–02:00, 21:00–24:00 Nov 7 00:00–02:00, 15:00–20:00 Nov 10 20:00–24:00 Nov 11 00:00–02:00, 16:00–22:00 Nov 12 21:00–24:00 Nov 13 00:00–02:00, 20:00–24:00 Nov 14 00:00–02:00, 13:00–19:00 Nov 17 15:00–20:00 Nov 18 20:00–24:00 Nov 19 00:00–01:00, 21:00–24:00 Nov 20 00:00–02:00, 20:00–24:00 Nov 21 00:00–03:00, 22:00–24:00 Nov 23 20:00–24:00 Nov 24 00:00–02:00, 21:00–24:00 Nov 25 00:00–02:00, 20:00–22:00 Nov 26 00:00–03:00, 21:00–24:00 Nov 27 00:00–02:00, 20:00–24:00 Nov 28 00:00–02:00, 18:00–24:00 Nov 29 00:00–01:00, 22:00–24:00 Nov 30 00:00–01:00, 19:00–22:00
December
Dec 1 21:00–24:00 Dec 2 00:00–02:00, 20:00–24:00 Dec 3 00:00–02:00, 20:00–24:00 Dec 4 00:00–02:00, 20:00–24:00 Dec 5 01:00–03:00, 15:00–20:00 Dec 7 20:00–24:00 Dec 8 20:00–24:00 Dec 9 00:00–02:00, 20:00–24:00 Dec 10 00:00–02:00, 20:00–24:00 Dec 11 00:00–02:00, 15:00–21:00 Dec 12 21:00–23:00 Dec 14 20:00–23:00 Dec 15 21:00–24:00 Dec 16 00:00–02:00, 20:00–24:00 Dec 17 00:00–02:00, 20:00–23:00 Dec 18 00:00–02:00, 15:00–20:00 Dec 21 20:00–24:00 Dec 22 00:00–02:00, 23:00–24:00 Dec 23 00:00–02:00 Dec 24 22:00–24:00 Dec 25 00:00–01:00, 20:00–24:00 Dec 26 00:00–02:00, 20:00–24:00 Dec 27 00:00–02:00, 21:00–24:00 Dec 28 20:00–24:00 Dec 29 00:00–02:00, 20:00–24:00 Dec 30 00:00–01:00, 17:00–19:00