In the July Sitv online newsletter, there was a short article about The Drop returning for a 4th season. I've been so busy lately, I completely forgot about the newsletter after I saw it until now. The article says The Drop will return with new episodes on Monday, July 24th. It does not explicitely say Jelynn will be returning for her 4th season as well, but there's a nice picture of her with the newsletter, so I can only assume she is staying with the show.
I'm glad she's staying with the show and that more episodes are being made. I'm just a little disappointed that I only realized this today (the 26th). Good thing there's weekend episodes.