I've done the same 45 visa on arrival from jan local extention 30 days and a boarder run 30 days up to May. Came back for 21 days in August got a tug . Told to many stamps and extention over the last 5 years through so I think your be fine . Got a new passport now back for 21 days no problem. But iam doing my retirement visa in January its much easier than the worry now.