I had to do that as well because a span of time was apparently missing( it actually wasn't) so I re-sent the same paper but also a note restating and clarifying the exact time period they said was missing. I've had delays all around because missing paperwork it took me four months to get SA (outland) because someone apparently dropped the ball. We finally called his MP who told us to resubmit everything (we did). I checked my email the next day for an unrelated reason and SA was there ( for my original application, it showed the date I re-sent it). I don't think it was a coincidence. Hopefully, that doesn't happen to you. Keep a copy of the letter it should have some info on it. Send the form(s) with a tracking number and signature required so at least your end is covered in case they say they didn't get and also so you can make sure they got it ( I didn't do that that time, BIG MISTAKE). So mine has taken nearly a year and isn't done yet
. I'd call your MP the day after the timeline said you should receive SA, that's my best advice. If you keep on them, they can't put you off and let it slide. It won't speed it up but hopefully you can learn from my mistake.