No, the Bill (which has now been passed by the Dail) will have no impact on your ability to issue a notice of termination on the grounds that you intend to sell the property at any time after 1 August 2020.
I wouldn't bother sending your tenants the suggested letter. Just send them the formal notice of termination next week - if your tenants want to leave early they can contact you.
Again, I would emphasise that you need to be very careful to comply with the necessary formalities in issuing the notice.