Answered by Gar:
I know the plan. It’s my plan. Respect the plan.
We’re doing one book per Doctor. Six, Seven and Nine have fewer adventures, but that lets us go into more detail.
The Eighth Doctor book will include a campaign that builds on all the other sourcebooks - one adventure per Doctor, in the style of that Doctor.
The Tenth Doctor may be expanded to the same bumper size as the Fourth Doctor book (240 pages instead of 160). Time will tell.
Oh, and we’re waiting until after the Christmas special before finishing off the writing of the Eleventh, so that’ll be in there too!