If the PON light is steady green on the FTTP ONT , then the Openreach part is pretty much done , the only proviso being that the correct serial number for your ONT is entered ( otherwise although the ONT is live ( PON light steady indicates this ) it could be associated with the wrong ISP , so in effect you have connected a BT router to ( for example ) a Talk Talk circuit ….IMHO , that is less likely than BT have yet to configure your new FTTP service at BT’s end….presumably someone who is upgrading to FTTP from FTTC or ADSL with the same ISP , it needs the ISP ( when OR confirm the work in physically done ) to remove the old FTTC or ADSL configuration and enter a new FTTP configuration, I don’t know if this has to be done after the OR visit ,or can be done in advance, but I suspect that your router is connected but you have no internet connection because your individual ‘profile’ ( access ) hasn’t been setup by BT yet ( or it’s done but with errors ) as already suggested, get onto the FTTP customer service number , they should be able to check this out , and also check your ONT serial number.
FYI, the OR cannot really guarantee to leave your FTTP line working , but they should be leaving it connected ( steady PON light ) with dozens of ISP using Openreach , if it’s the ISP failure to do some work at their ‘end’ that is stopping you getting on line , all the OR tech can really do is advise the consumer to contact their ISP, and if they were able to ring up ‘BT’ and make enquiries on behalf of a BT customer they would have to offer the same level of service to every other ISP that uses OR, otherwise they get accused of favouring BT
