Travel to the europe

Hi, I am a Georgian national and recently naturalised as British. I received certificate of naturalisation but have not applied for the British passport yet. Now is too late as that would take 6 weeks but I have to travel now for the work occasion to the Europe. Georgians have rights for free movement to Europe thus can travel using my Georgian passport but concerned how it going to be on the way back to the UK ??
I have sent my latest biometric ID Card to home office to be destroyed as was required to do so after I received the certificate of naturalisation. But somehow I still have the previous ID Card which is still valid (expire date is 2021). Do you think I can still use that as my ID on my way back to the UK ( I am might asking a silly question but try not to miss this trip)? Do you think I will get much trouble not permitting to cross the border back or get a penalty? What do you think what consequences could be in such case if I still travel and will be coming back ? Might there could be some exceptions in my case and they will let me cross the border because I am already the British citizen and live & work here??
Thanks in advance

Your old BRPs are all invalid for entry to the UK. Certificate of naturalisation is also NOT a travel document. British passport is required for travel. You may use your valid BRP to board a plane back to the UK and get to the UK border but then you must show the certificate of naturalisation to the officer. Expect questioning and long delays at the airport if you choose to do this

Don't travel back to the UK as a UK citizen on foreign passport and BRP.

That BRP you are supposed to give back to the Home Office upon naturalization. If you use it to travel, it will be seized from you and that can open a big can of worms. You don't want that. Even if you use it only to get in the plane, they will still know about it (Advanced passenger information!). You can't just hide it and claim you don't have it and you've been let in the plane just like that.

Apply for your British passport, then when you get it, travel a much as you wish.

Hi Zimba, thanks for your reply, appreciated.
Actually I call to the uk border force at Gatwick and have spoken to the officer over the phone. He told me the same: I should have with me all these three documents (Geo passport, the previous BRP Card and the certificate of naturalisation) with me. On the way back to the UK I will show to the European border officers my Geo passport and the previous BRP Card, then they will let me get into airplane. After I arrived back in the UK I need to present all three documents to the British border officer and explain the situation. They will keep the BRP Card and let me get in. This will might take more time then usual. but I am fine with that as far as I will be allowed to cross the border. Additionally, he told me that if I didn’t have this previous BRP Card and travel to the Europe with Geo passport only then I wouldn’t be able to take flight from The Europe back to the UK, because they need to see a document showing my settlement status in the UK and the BRP Card does that. Lucky that the card itself is still valid till 2021.
So will be taking flight tomorrow.

Many thanks again.

The advice given is accurate. British citizens are not subject to immigration control. So as long you prove you are British you will be fine. What you are doing is not advised but it works. Your BRP will be taken from you. Explain that you wanted to return it but an urgent travel came up and you could not apply for passport in time.

Many thanks Zimba again. actually I had a time before to apply for passport but couldn’t actually take a picture because had some problem related to the facial skin (sorry for the details) I have the letters from my dermatologist. I was just waiting for the problem to be sorted and only then would be able to take that. Old pictures by requirement was not allowed to use for the passport and that is all.

Might do need to go with such details with them and will take your advice.

Thanks again