Yes the filler will obvious end before July, the only question is will they stretch it all the way to the very last week of June?
The ending theme will change again on the first week of July, that week also signifies the middle of this season.
If they really do stretch it to the final week of June, then the anime team are huge dicks for showing Madara and stuff in the current ending, because that means this entire ending would be wasted on fillers. So I think they will end it in early June instead of late June.