My customers had a choice to get upgrades and most chose that option. I don’t have any intention of charging another fee for people to access the online version because I’m just changing the delivery format.
Having a membership site just makes it easier to update the content and gives people a means of accessing the new delivery method. One day I will dive into membership sites but not with my baby

I agree with Art about starting a membership site. It doesn’t have to be fixed term necessarily though, especially if you feel that you will be constantly updating the info. Afterall, any info. based on changing technology lends itself to continuous update, especially if the person maintaining the information wants to keep readers in-the-know. I would mention that the member would be paying to access not only to the ebook as it is now, but for all updates and additions as well. In otherwords, if you were ever to release version 2 of the ebook with updates, members would not have to purchase it as they would have access via your membership site as long as they paid for continued access. Unless information in the ebook that needs updating would be misleading or cause issues for your readers if you released it as-is right now, you could put up the membership site, release parts of the book on the site at intervals (a chapter/section each week or month, etc), then release the updates as additional modules/sections for the members. Or, you could do as I have outlined here, editing the information in the book as it becomes time for that section to be released on the site. This would give you time to spread all of the dreaded work out over time. If you got ambitious and knocked out a bunch of update edits at once, you would just have some of your membership site releases ready ahead of time.

You could charge people a monthly fee or a one time lifetime fee. The only thing I would suggest is that you provide a much reduced or free way for people who already paid for your ebook to access the membership site. Given that your existing ebook has so many pages, if you released sections of these pages at weekly intervals, you would have plenty of time to write updates and additional information for later release.

Yaro Starak is actually an expert on this subject. I read his blog all the time. He actually has a membership site wherein he teaches people how to create a successful membership site. I haven’t done it yet, but hope to soon. It is not cheap, but from what I have read, is worth it. That I am aware of, he has 2 or 3 successful membership sites going. And for the record, I have nothing to do with Yaro at present (am not an affiliate, don’t work for him), I am just a fan. Hope this info helps. If you have any questions about what I have said here, you can email me. Good luck:)