If you have approval for a pump, your best bet is to talk to your diabetes team. Do you know OmniPod is on offer in your CCG? My CCG has decided it is too expensive so do not offer it to anyone.
If you are lucky and it is on offer for you, they will know best when they (not the country .. because it may vary) will have access to OmniPod 5. Given the design of the OmniPod, I understand that they will offer an upgrade to all current OmniPod users when the new version is released.
If it is not available in your CCG, it is very difficult to get them to offer it and it is best to focus on what they offer.
BTW what is it about the OmniPod 5 that makes you think it is the ideal one for you? The features you want may be available on other pumps.