Given those whose contracts end officially on June 30 2021 are effectively still under contract, then July 1st is when questions can be legitimately asked or released lists issued.It is true players can leave or be released before then but there is effectively a grace period between end of season and end of contract when negotiations can be carried out. And players do have 'holiday' periods when a season ends, even if this year may involve "staycations". We can't be expected to be spoon-fed minute by minute day by day negotiation detail.
And last year, on 24th June, Tranmere published this
https://www.tranmererovers.co.uk/news/2020/june/squad-update/
So maybe something similar will happen around that time of this month given that Micky will have had time to assess the situation.