I have a website that I recently overhauled last year using CoffeeCup HTML Editor (Paid Version) in modifying a responsive website template to serve my needs. Long story short, having spent countless hours tweaking performance, SEO, mobile and secuity, while I am satisfied in having been able to finally achieve a score of 100 in hubspot website grader, I would be interested to know if anyone of you has taken the plunge to migrate their website from bootstrap version 3 to version 4 without having to spend an inordinate amount of time in doing so and the steps taken to accomplish what appears to be a formidable and somewhat overwhelming task to begin with. Also, after all is said and done, do you feel the migration from bootstrap version 3 to 4 is worth doing for an existing website that was created and relies essentially upon bootstrap version 3? For those interested, my website is inspectabuilding.com. Thank you ahead of time.

I don't know exactly when, but it will be soon that Bootstrap will be updating to version 5. Why not wait on 4 and go to 5 when it comes out.

If as you say, with bootstrap version 5 in the offing, makes sense to wait and migrate to version 5 rather than take the time to migrate to version 4.

Well, I'm a newbie with most of cc's applications, so I can't tell you what to do. Here's a link to Bootstraps blog. https://blog.getbootstrap.com/ I hope that helps you make the decision.