The short answer is at least 3 times. The longer answer is explained with the following example:

Let's say I've just posted my 5 album batch in May, and it’s time to start thinking about the June batch. If everything goes smoothly and I update as expected, I hold to the following schedule:

By June 1: I have listened to each album at least once, and preferably am cycling through them a second time.
By June 8: I have given each album a second listen and have started round 3.
By June 12: I have given each album a third listen.
June 13th to 18th: I listen again to each album as many times as I feel necessary to get my thoughts in order. If it's an album I already know well the three listens are enough. In other cases, I will listen to it repeatedly in part or full until I feel like I've maxed out on what I can absorb. Once I've finished a review for an album, I stop listening to it and shift my focus to the remaining ones, listening as much as needed, before I finish the batch.