I second this. And it's brilliant that there is actually a precedent of treating a collection of box sets as one series consisting of individual volumes. So there is no need to invent how this should be treated. It would be good to work out a policy for distinguishing anthologies from series. Especially given that Nick Briggs said in an interview he prefers the box format and would want to move other ranges to it too.
I thought that there is no functional distinction between the two, just the page title. But the example of Jago and Litefoot shows that I was wrong: each anthology has its own page whereas all box sets of an audio series live on the same page. (Off topic: something is wrong with the box set images of Jago and Litefoot.)
Here are some obvious candidates for a "series" treatment:
- Dark Eyes - Dark Eyes 4
- Doom Coalition 1 and further releases
- Extinction and further releases
- Only the Monstrous and further releases of The War Doctor series
- The Diary of River Song and further releases
What they all have in common is a common series name on the box and either a numeric designation (starting from the 2nd box in case of Dark Eyes and absent in case of UNIT) or a status as a range of audios on the BF website (absent so far in the case of the War Doctor, as "Collected" is not a range in the proper sense). Are there other examples I've missed?
My suggestion is to use seriality, i.e., the presence of several box sets under a common name/range, as the primary criterion for something being a "series" rather than an "anthology". For instance, we know Doom Coalition 2 will be released and, hence, can already organize Doom Coalition as a series page without mentioning the 2nd volume. On the other hand, The Third Doctor Adventures may be too early to treat as a series. Let it stay an anthology for now.
Skipping the obvious anthologies like The Company of Friends, there are less clear cut cases when a box set for a particular doctor is named Volume 01 but is released within a larger range, perhaps with other releases in between. However, I was not able to find any example that would already be in Volume 02 stage. So maybe this does not have to be decided now.