Lifetime ISA - Bonus Payment Times

Hi Everyone

Got a LISA question and can not seem to find an answer anywhere.

My partner and myself both have a LISA. I opened mine last March with £1 and have put £4k in as a lump sum last month. My partners LISA was opened last month and we put another £4k straight into it. I am fairly sure that my partners bonus will get paid in a year after the account has been open, but when does it get paid after the account has been open for more than a year?

I can not work out if I have to wait every year for the bonus to be paid? Also, how does it work if we found a house and the account was say 2 years and a month old? My thinking is this:
LISA Year 1 - April 2018-March 2019 - £4k deposited in this time + £1k bonus payment = £5k total
LISA Year 2 - April 2019-March 2020 - Another £4k deposited + £1k bonus payment = £5k + the £5k already in there
Then in April 2020 deposit another £4k, but this time lets say I find a house in May 2020, would I get another £1k bonus payment as I have put the whole years allowance in?

Can not find much information regarding how the payments work. We are both with Skipton Building Society and our accounts are effectively mirrors (with the exception of mine being open a year longer but with no action until recently). Obviously trying to maximise the bonus payments if we can for a move date in approximately 2.5 years .

Any help would be greatly appreciated .