Most often in January, 31 days.
Highest follower count seen that year: 83,488.
January
Jan 1 22:00–24:00 Jan 2 00:00–01:00, 11:00–15:00 Jan 3 11:00–15:00, 22:00–24:00 Jan 4 00:00–01:00, 12:00–16:00, 22:00–24:00 Jan 5 00:00–02:00 Jan 6 15:00–17:00, 22:00–24:00 Jan 7 00:00–02:00, 14:00–17:00, 22:00–24:00 Jan 8 00:00–01:00, 13:00–16:00 Jan 9 16:00–17:00, 22:00–24:00 Jan 10 00:00–02:00, 14:00–17:00, 22:00–24:00 Jan 11 13:00–17:00, 21:00–24:00 Jan 12 00:00–01:00, 14:00–17:00, 21:00–24:00 Jan 13 00:00–02:00, 13:00–17:00, 22:00–24:00 Jan 14 15:00–17:00, 22:00–24:00 Jan 15 00:00–01:00, 14:00–16:00, 22:00–24:00 Jan 16 00:00–01:00, 14:00–17:00, 22:00–24:00 Jan 17 00:00–01:00, 14:00–16:00 Jan 18 15:00–17:00, 22:00–23:00 Jan 19 00:00–02:00, 14:00–17:00 Jan 20 14:00–17:00, 22:00–24:00 Jan 21 00:00–03:00, 16:00–17:00, 22:00–24:00 Jan 22 00:00–01:00, 14:00–17:00, 22:00–24:00 Jan 23 00:00–01:00, 14:00–17:00 Jan 24 14:00–17:00, 22:00–24:00 Jan 25 14:00–16:00, 22:00–24:00 Jan 26 00:00–01:00, 14:00–17:00, 22:00–24:00 Jan 27 00:00–01:00, 14:00–17:00, 22:00–24:00 Jan 28 00:00–02:00, 14:00–17:00 Jan 29 01:00–03:00, 14:00–17:00 Jan 30 14:00–17:00, 22:00–24:00 Jan 31 00:00–01:00, 14:00–17:00
February
Feb 1 14:00–17:00, 22:00–24:00 Feb 2 00:00–02:00 Feb 5 14:00–17:00, 22:00–24:00 Feb 6 00:00–01:00, 14:00–18:00, 23:00–24:00 Feb 7 00:00–01:00, 15:00–17:00 Feb 8 14:00–17:00, 23:00–24:00 Feb 9 00:00–02:00, 14:00–17:00 Feb 10 15:00–17:00, 22:00–24:00 Feb 11 15:00–17:00 Feb 12 14:00–17:00, 22:00–24:00 Feb 13 00:00–01:00, 15:00–17:00, 22:00–24:00 Feb 14 00:00–01:00 Feb 15 14:00–17:00, 22:00–24:00 Feb 16 00:00–01:00, 15:00–17:00 Feb 17 15:00–17:00, 22:00–24:00 Feb 18 00:00–01:00 Feb 19 15:00–17:00, 22:00–24:00 Feb 20 00:00–01:00, 14:00–17:00, 22:00–24:00 Feb 21 00:00–01:00, 14:00–17:00 Feb 22 15:00–17:00 Feb 23 14:00–17:00, 22:00–24:00 Feb 24 00:00–01:00, 13:00–16:00 Feb 25 22:00–24:00 Feb 26 00:00–01:00, 14:00–17:00, 22:00–24:00 Feb 27 00:00–01:00, 15:00–17:00
March
Mar 1 14:00–17:00 Mar 2 14:00–16:00, 22:00–24:00 Mar 3 00:00–01:00 Mar 5 15:00–16:00 Mar 6 14:00–17:00, 22:00–24:00 Mar 7 00:00–01:00, 14:00–17:00, 22:00–24:00 Mar 8 00:00–01:00, 15:00–17:00, 22:00–24:00 Mar 9 00:00–01:00, 15:00–17:00, 22:00–24:00 Mar 10 00:00–01:00 Mar 11 15:00–17:00 Mar 12 14:00–17:00, 22:00–24:00 Mar 13 00:00–02:00, 15:00–17:00 Mar 14 22:00–24:00 Mar 15 15:00–18:00 Mar 16 12:00–14:00 Mar 17 13:00–17:00, 22:00–24:00 Mar 18 00:00–01:00, 22:00–24:00 Mar 19 00:00–01:00, 14:00–17:00, 23:00–24:00 Mar 20 00:00–02:00, 14:00–17:00 Mar 21 15:00–17:00, 22:00–24:00 Mar 22 15:00–17:00 Mar 23 14:00–17:00, 22:00–24:00 Mar 24 00:00–01:00, 12:00–17:00 Mar 25 13:00–17:00 Mar 26 13:00–17:00, 22:00–24:00 Mar 27 00:00–01:00, 22:00–24:00 Mar 28 00:00–01:00, 14:00–17:00 Mar 29 13:00–17:00, 21:00–24:00 Mar 30 21:00–23:00
April
Apr 1 13:00–17:00 Apr 2 13:00–17:00, 21:00–24:00 Apr 3 14:00–16:00 Apr 4 13:00–16:00, 21:00–24:00 Apr 5 21:00–24:00 Apr 7 13:00–16:00, 21:00–23:00 Apr 8 12:00–16:00 Apr 9 22:00–24:00 Apr 10 11:00–16:00 Apr 11 14:00–16:00, 21:00–24:00 Apr 12 00:00–01:00, 13:00–16:00, 21:00–24:00 Apr 13 00:00–01:00, 14:00–16:00, 21:00–24:00 Apr 14 22:00–24:00 Apr 15 14:00–16:00, 21:00–24:00 Apr 16 13:00–16:00, 21:00–24:00 Apr 17 21:00–24:00 Apr 18 00:00–01:00, 13:00–17:00, 21:00–24:00 Apr 19 13:00–16:00, 21:00–24:00 Apr 20 00:00–01:00, 14:00–16:00, 21:00–24:00 Apr 21 21:00–24:00 Apr 22 11:00–16:00, 21:00–24:00 Apr 23 13:00–16:00, 21:00–24:00 Apr 24 21:00–23:00 Apr 25 21:00–24:00 Apr 26 14:00–16:00, 21:00–23:00 Apr 28 21:00–24:00 Apr 29 13:00–16:00, 21:00–24:00 Apr 30 15:00–16:00, 21:00–24:00
May
May 1 13:00–16:00, 21:00–24:00 May 2 14:00–16:00, 22:00–24:00 May 3 00:00–01:00, 14:00–16:00, 21:00–23:00 May 4 14:00–16:00, 21:00–24:00 May 5 14:00–16:00 May 6 11:00–12:00, 14:00–15:00, 21:00–24:00 May 7 00:00–01:00, 14:00–16:00 May 8 13:00–14:00, 20:00–24:00 May 9 14:00–16:00, 21:00–23:00 May 10 13:00–16:00, 21:00–23:00 May 11 13:00–16:00 May 12 14:00–15:00, 21:00–24:00 May 13 14:00–16:00, 21:00–24:00 May 14 14:00–15:00 May 15 13:00–16:00, 21:00–24:00 May 16 14:00–16:00, 21:00–24:00 May 17 13:00–16:00, 21:00–24:00 May 18 13:00–16:00, 21:00–24:00 May 19 14:00–16:00, 21:00–24:00 May 20 13:00–14:00, 21:00–22:00 May 22 14:00–16:00, 21:00–24:00 May 23 21:00–24:00 May 24 13:00–16:00, 21:00–24:00 May 25 14:00–16:00, 21:00–24:00 May 29 14:00–16:00, 21:00–23:00 May 30 14:00–16:00, 21:00–24:00 May 31 12:00–16:00, 21:00–24:00
June
Jun 1 13:00–15:00 Jun 2 13:00–16:00, 22:00–24:00 Jun 3 14:00–16:00, 21:00–24:00 Jun 5 13:00–16:00, 22:00–24:00 Jun 6 00:00–01:00, 12:00–16:00, 21:00–24:00 Jun 7 00:00–01:00, 14:00–15:00 Jun 8 13:00–16:00, 21:00–24:00 Jun 9 13:00–16:00, 21:00–23:00 Jun 10 13:00–16:00, 21:00–24:00 Jun 12 14:00–16:00, 21:00–24:00 Jun 13 00:00–01:00, 14:00–16:00 Jun 15 13:00–16:00, 20:00–24:00 Jun 16 13:00–15:00, 21:00–23:00 Jun 18 14:00–16:00, 20:00–24:00 Jun 19 13:00–16:00, 20:00–24:00 Jun 20 14:00–16:00, 21:00–24:00 Jun 23 14:00–16:00 Jun 24 14:00–16:00 Jun 25 14:00–16:00, 20:00–23:00 Jun 27 13:00–16:00, 21:00–24:00 Jun 28 14:00–16:00, 22:00–24:00 Jun 29 00:00–01:00, 21:00–24:00 Jun 30 14:00–16:00, 21:00–24:00
July
Jul 1 21:00–24:00 Jul 2 22:00–24:00 Jul 3 00:00–01:00, 14:00–16:00, 21:00–24:00 Jul 4 12:00–16:00, 20:00–24:00 Jul 5 13:00–16:00, 21:00–24:00 Jul 6 15:00–16:00, 21:00–24:00 Jul 7 13:00–16:00, 21:00–23:00 Jul 8 13:00–15:00 Jul 9 08:00–10:00, 14:00–16:00, 21:00–23:00 Jul 10 08:00–10:00, 14:00–16:00, 20:00–24:00 Jul 11 09:00–10:00, 22:00–24:00 Jul 12 00:00–01:00, 09:00–10:00, 13:00–16:00, 21:00–24:00 Jul 13 12:00–16:00 Jul 15 14:00–16:00 Jul 16 08:00–10:00, 14:00–16:00 Jul 17 14:00–16:00, 21:00–24:00 Jul 18 13:00–16:00 Jul 19 10:00–11:00, 13:00–16:00, 20:00–24:00 Jul 20 14:00–18:00 Jul 22 14:00–17:00 Jul 23 15:00–18:00, 22:00–24:00 Jul 24 00:00–02:00, 13:00–16:00, 22:00–24:00 Jul 25 00:00–01:00, 13:00–17:00, 21:00–24:00 Jul 26 00:00–01:00, 13:00–15:00, 21:00–24:00 Jul 27 14:00–15:00