Most often in April, 27 days.
Highest follower count seen that year: 7,891.
January
Jan 17 15:00–17:00 Jan 18 08:00–12:00, 14:00–16:00 Jan 19 08:00–13:00 Jan 20 09:00–12:00, 14:00–16:00 Jan 21 09:00–13:00 Jan 24 13:00–18:00 Jan 25 09:00–15:00 Jan 26 11:00–14:00 Jan 27 12:00–16:00 Jan 28 13:00–18:00 Jan 29 10:00–14:00 Jan 31 15:00–18:00
February
Feb 1 10:00–15:00 Feb 2 09:00–14:00 Feb 3 08:00–13:00 Feb 4 10:00–14:00 Feb 5 09:00–14:00 Feb 6 09:00–10:00, 12:00–17:00 Feb 7 09:00–14:00 Feb 8 09:00–13:00 Feb 10 16:00–19:00 Feb 11 15:00–19:00 Feb 12 06:00–07:00, 16:00–18:00 Feb 13 13:00–18:00 Feb 14 09:00–14:00 Feb 15 12:00–17:00 Feb 17 11:00–15:00 Feb 18 09:00–13:00, 15:00–17:00 Feb 19 15:00–18:00 Feb 20 10:00–15:00 Feb 21 09:00–14:00 Feb 22 09:00–15:00 Feb 23 07:00–08:00 Feb 24 07:00–09:00, 12:00–16:00 Feb 26 07:00–09:00, 12:00–16:00 Feb 27 15:00–16:00 Feb 28 10:00–15:00
March
Mar 1 09:00–14:00 Mar 2 08:00–10:00 Mar 3 14:00–17:00 Mar 4 15:00–17:00 Mar 5 11:00–16:00 Mar 6 09:00–12:00, 15:00–17:00 Mar 7 09:00–14:00 Mar 8 08:00–13:00 Mar 10 07:00–08:00, 16:00–18:00 Mar 11 08:00–10:00, 14:00–17:00 Mar 12 07:00–11:00, 16:00–18:00 Mar 13 08:00–12:00, 16:00–18:00 Mar 14 10:00–16:00 Mar 15 09:00–14:00 Mar 17 13:00–19:00 Mar 18 11:00–16:00 Mar 19 13:00–19:00 Mar 20 08:00–13:00 Mar 21 11:00–17:00 Mar 22 09:00–15:00 Mar 24 08:00–13:00 Mar 25 07:00–11:00, 14:00–17:00 Mar 26 08:00–13:00, 17:00–19:00 Mar 27 08:00–12:00, 14:00–17:00 Mar 28 10:00–15:00 Mar 29 08:00–13:00 Mar 31 11:00–14:00
April
Apr 1 08:00–12:00, 15:00–17:00 Apr 2 09:00–14:00 Apr 3 10:00–16:00 Apr 4 10:00–15:00 Apr 5 09:00–14:00 Apr 7 06:00–08:00, 12:00–16:00 Apr 8 10:00–16:00 Apr 9 10:00–16:00 Apr 10 09:00–14:00 Apr 11 07:00–13:00 Apr 12 06:00–11:00 Apr 13 10:00–13:00 Apr 14 08:00–13:00 Apr 15 08:00–11:00, 17:00–18:00 Apr 16 08:00–14:00 Apr 17 07:00–10:00, 15:00–18:00 Apr 18 09:00–15:00 Apr 19 09:00–14:00 Apr 21 11:00–17:00 Apr 22 09:00–12:00, 16:00–18:00 Apr 23 07:00–08:00, 13:00–17:00 Apr 24 07:00–13:00 Apr 26 11:00–16:00 Apr 27 09:00–12:00 Apr 28 12:00–17:00 Apr 29 08:00–10:00, 13:00–16:00 Apr 30 08:00–13:00
May
May 1 09:00–15:00 May 2 10:00–15:00 May 3 09:00–14:00 May 5 07:00–08:00, 11:00–15:00 May 6 11:00–17:00 May 7 06:00–08:00, 14:00–17:00 May 8 13:00–17:00 May 9 07:00–13:00 May 10 07:00–10:00 May 11 07:00–11:00, 14:00–16:00 May 12 11:00–16:00 May 13 08:00–14:00 May 14 10:00–15:00 May 15 10:00–14:00 May 16 09:00–14:00 May 17 10:00–15:00 May 19 06:00–08:00, 11:00–15:00 May 20 10:00–15:00
June
Jun 7 08:00–13:00 Jun 9 11:00–16:00 Jun 10 07:00–12:00 Jun 11 06:00–11:00 Jun 12 06:00–10:00 Jun 13 05:00–10:00 Jun 15 07:00–09:00 Jun 16 07:00–10:00 Jun 17 07:00–09:00, 13:00–15:00 Jun 19 06:00–09:00, 11:00–14:00 Jun 20 08:00–13:00 Jun 21 14:00–17:00 Jun 22 10:00–14:00 Jun 23 08:00–13:00 Jun 24 07:00–12:00 Jun 25 08:00–12:00 Jun 26 10:00–13:00 Jun 27 07:00–09:00 Jun 29 08:00–11:00 Jun 30 09:00–14:00
July
Jul 1 07:00–12:00 Jul 2 08:00–13:00 Jul 3 06:00–10:00 Jul 4 06:00–11:00 Jul 5 08:00–12:00 Jul 7 06:00–12:00 Jul 8 06:00–12:00 Jul 9 05:00–10:00 Jul 10 07:00–10:00 Jul 13 07:00–13:00 Jul 14 08:00–13:00 Jul 15 08:00–13:00 Jul 16 07:00–11:00 Jul 17 07:00–13:00 Jul 18 08:00–13:00 Jul 19 08:00–11:00 Jul 20 07:00–13:00 Jul 21 09:00–12:00 Jul 22 08:00–13:00 Jul 23 08:00–13:00 Jul 24 07:00–13:00 Jul 25 08:00–13:00 Jul 26 07:00–10:00 Jul 27 07:00–13:00