Dangers of up keeping up with the Angular release schedule?

[Kyle S]

Hello all,

My company is exploring Angular2+ as a technology for a large, complex application.

Our development cycle is much longer than Angular's release cycle, and we don't expect to be able to manage doing upgrades every 6 (or even every 18) months.

What sort of issues would we likely encounter by choosing to stay on an old version and not upgrading?

Will updated browsers eventually stop being able to support our application?
Any other complications come to mind?

Would AngularJS be a better choice in this scenario?

Thanks