Got the Reserve card in October right after the announcement about the 2020 changes. Mrs Lov2Fly also got the Reserve card within a day or so of the announcement.
We both hit the required spend in October before our first statements in mid November.
My miles posted the day after my statement was issued. Mrs Lov2Fly’s bunds was posted in October - before her first statement was issued.
Good luck - hope you can get it figured out.