Proof of residence for a year "doing nothing"

I'm prepping my application (probably going with the online route), and it says that I need to submit proof of residence by virtue of letters from employers, government, etc.

Timeline looks like this:

• Oct 2012 to Sep 2013: Study -> Letter from uni as proof
• Sep 2013 to May 2014: Did nothing (worked on PhD application), no benefits, no study, no work, ...
• May 2014 to Oct 2014: Worked -> Payslips as proof
• Oct 2014 to Jan 2015: Supposed to study but deferred because I had an accident -> Letters from hospital and ESA letters as proof
• Jan 2015 to present: Study -> Letter from uni as proof

So this seems pretty straight forward to me, except that period from Sep 2013 to May 2013. Basically I hadn't got PhD funding, so decided to just take the year and work on a new proposal. I didn't do anything else during that time, just lived off my savings and for 3 months at some point attended a once a week Welsh class, but nothing else. I had thought I could ask the old landlord for a letter, but we sadly didn't part on good terms and he won't reply. The online form says that bank statements are not acceptable, so I'm really stumped for what else I could submit? Any suggestions?

(I got my PR document issued on 31 Mar 2014 btw, if that helps).

Any help would be highly appreciated. Thank you.

See also Absences.

A difficulty is that without entry nor exit stamps in the passports and limited exit checks, no one can easily tell, without alternative evidence, if the holder was present or absent, in or from the UK respectively, during a particular period.

If the UK Border Force kept arrival records of everyone entering the UK, then it would be easy for them to verify that you hadn’t entered the UK recently.

If you are a non-EU national your passport stamps cover the evidence of stay.

Thanks. Yes, I'm EU so there are no stamps in my passport (I didn't even have a passport until two years ago...).

So I suppose the best I can do is to accumulate as many documents to make a plausible case from that period? I mean, I applied for PR during that time, so have two letters about this from HO, I have a certificate from the Welsh course that covers part of that period and I just thought I could also ask the parish priest from the church I went to during that time if he could briefly write to confirm that I regularly attended the parish at that time (hopefully they'll remember me or have records..). I could supply bank statements just as supplementary evidence I guess, even if they say on the form that they are not sufficient to prove having been present. What do you think about this, is this highly risky with only these documents as evidence? I'm especially concerned about that as that would be the start of the five year period so I suppose they'd make doubly sure that I was here?