Most often in May, 31 days.
Highest follower count seen that year: 9,278.
January
Jan 3 03:00–10:00 Jan 4 04:00–11:00 Jan 5 05:00–10:00 Jan 6 04:00–11:00 Jan 8 03:00–10:00 Jan 9 03:00–11:00 Jan 10 03:00–11:00 Jan 12 05:00–11:00 Jan 13 03:00–10:00 Jan 14 04:00–11:00 Jan 15 04:00–11:00 Jan 17 04:00–10:00 Jan 19 05:00–10:00 Jan 21 03:00–10:00 Jan 22 03:00–10:00 Jan 23 04:00–10:00 Jan 24 05:00–11:00 Jan 25 04:00–11:00 Jan 26 05:00–11:00 Jan 27 04:00–11:00 Jan 29 03:00–09:00 Jan 30 04:00–11:00 Jan 31 05:00–11:00
February
Feb 1 04:00–11:00 Feb 2 05:00–10:00 Feb 7 03:00–11:00 Feb 8 04:00–11:00 Feb 9 05:00–10:00 Feb 10 03:00–11:00 Feb 12 03:00–09:00 Feb 13 05:00–11:00 Feb 14 05:00–11:00 Feb 15 04:00–11:00 Feb 16 05:00–11:00 Feb 17 03:00–10:00 Feb 20 03:00–11:00 Feb 21 04:00–11:00 Feb 23 05:00–11:00 Feb 24 04:00–11:00 Feb 25 04:00–11:00 Feb 26 04:00–10:00 Feb 27 03:00–10:00
March
Mar 4 03:00–11:00 Mar 5 04:00–11:00 Mar 7 03:00–11:00 Mar 8 05:00–11:00 Mar 9 05:00–11:00 Mar 10 04:00–11:00 Mar 11 04:00–11:00 Mar 12 03:00–10:00 Mar 13 04:00–11:00 Mar 14 04:00–11:00 Mar 15 04:00–11:00 Mar 16 05:00–10:00 Mar 18 03:00–11:00 Mar 21 03:00–10:00 Mar 22 03:00–11:00 Mar 23 05:00–11:00 Mar 24 04:00–10:00 Mar 25 03:00–10:00 Mar 26 04:00–11:00 Mar 27 04:00–10:00 Mar 28 04:00–11:00 Mar 29 04:00–11:00 Mar 30 05:00–11:00 Mar 31 05:00–11:00
April
Apr 1 04:00–11:00 Apr 3 04:00–10:00 Apr 4 04:00–11:00 Apr 5 04:00–10:00 Apr 6 05:00–11:00 Apr 8 04:00–11:00 Apr 9 04:00–11:00, 22:00–24:00 Apr 10 00:00–03:00 Apr 12 03:00–11:00 Apr 13 05:00–11:00 Apr 14 03:00–11:00 Apr 16 04:00–11:00, 20:00–24:00 Apr 17 00:00–03:00, 20:00–24:00 Apr 18 00:00–03:00, 20:00–24:00 Apr 19 00:00–03:00, 23:00–24:00 Apr 20 00:00–05:00 Apr 21 19:00–24:00 Apr 22 00:00–02:00, 20:00–24:00 Apr 23 00:00–03:00, 20:00–24:00 Apr 24 00:00–01:00, 19:00–24:00 Apr 25 00:00–02:00, 21:00–24:00 Apr 26 00:00–04:00 Apr 27 21:00–24:00 Apr 28 00:00–03:00, 20:00–24:00 Apr 29 00:00–03:00, 20:00–24:00 Apr 30 00:00–04:00, 20:00–24:00
May
May 1 00:00–03:00, 20:00–24:00 May 2 00:00–02:00 May 3 00:00–04:00 May 4 20:00–24:00 May 5 00:00–03:00, 20:00–24:00 May 6 00:00–02:00, 21:00–24:00 May 7 00:00–03:00, 20:00–21:00 May 8 19:00–24:00 May 9 21:00–24:00 May 10 00:00–03:00 May 11 20:00–24:00 May 12 00:00–03:00, 20:00–24:00 May 13 00:00–03:00, 20:00–24:00 May 14 00:00–01:00, 21:00–24:00 May 15 00:00–03:00, 20:00–23:00 May 16 00:00–02:00, 21:00–24:00 May 17 00:00–03:00, 18:00–24:00 May 18 19:00–24:00 May 19 00:00–02:00 May 20 20:00–22:00 May 21 01:00–03:00, 20:00–24:00 May 22 00:00–03:00, 20:00–24:00 May 23 00:00–02:00 May 24 18:00–24:00 May 25 20:00–24:00 May 26 00:00–03:00, 20:00–24:00 May 27 00:00–03:00, 20:00–24:00 May 28 00:00–03:00, 20:00–24:00 May 29 00:00–03:00, 18:00–23:00 May 30 20:00–24:00 May 31 00:00–03:00, 18:00–23:00
June
Jun 1 20:00–24:00 Jun 2 00:00–03:00, 20:00–24:00 Jun 3 00:00–03:00, 20:00–24:00 Jun 4 00:00–03:00 Jun 5 23:00–24:00 Jun 6 21:00–24:00 Jun 7 00:00–04:00 Jun 8 20:00–24:00 Jun 9 00:00–02:00, 12:00–20:00 Jun 10 21:00–24:00 Jun 11 00:00–04:00, 21:00–24:00 Jun 12 00:00–05:00, 21:00–24:00 Jun 13 00:00–03:00 Jun 15 20:00–24:00 Jun 16 00:00–02:00 Jun 17 20:00–24:00 Jun 18 01:00–02:00, 20:00–24:00 Jun 19 00:00–04:00 Jun 20 20:00–24:00 Jun 21 00:00–03:00, 18:00–24:00 Jun 22 20:00–24:00 Jun 23 00:00–01:00, 22:00–24:00 Jun 24 01:00–03:00, 21:00–24:00 Jun 25 00:00–03:00, 21:00–24:00 Jun 26 00:00–04:00, 20:00–24:00 Jun 27 00:00–05:00, 11:00–18:00 Jun 28 18:00–23:00 Jun 29 21:00–24:00 Jun 30 00:00–04:00, 20:00–24:00
July
Jul 1 00:00–03:00, 19:00–24:00 Jul 2 00:00–02:00, 20:00–24:00 Jul 3 00:00–03:00, 20:00–24:00 Jul 4 00:00–02:00 Jul 6 20:00–24:00 Jul 7 00:00–03:00, 21:00–24:00 Jul 8 00:00–03:00, 20:00–24:00 Jul 9 00:00–04:00, 21:00–24:00 Jul 10 00:00–04:00, 21:00–24:00 Jul 11 00:00–04:00, 20:00–24:00 Jul 12 00:00–03:00, 23:00–24:00 Jul 13 00:00–05:00, 21:00–24:00 Jul 14 00:00–03:00, 21:00–24:00 Jul 15 00:00–03:00, 22:00–24:00 Jul 16 00:00–04:00 Jul 17 22:00–24:00 Jul 18 00:00–06:00, 21:00–24:00 Jul 19 00:00–04:00 Jul 20 23:00–24:00 Jul 21 00:00–03:00, 21:00–24:00 Jul 22 00:00–03:00, 22:00–24:00 Jul 23 00:00–06:00 Jul 24 00:00–04:00, 23:00–24:00 Jul 25 00:00–03:00 Jul 30 21:00–23:00