Is it possible to set up a new intercom unit with old keys?

Question

Programming

The other day, an announcement appeared on the entrance door from a company servicing intercoms, which reported that due to a breakdown, a block had been replaced with a new one. Because of this, I now need to go to their office to buy new keys. This annoys me, because you need to travel far enough, and even during working hours. In addition, there is a suspicion that they could program the new block with the old keys and we would not notice anything at all. If so, then this is a scam.

Answer 1

Most likely, it is possible to "register" old keys into the new intercom. But this should be done at your doorstep, and for free.
And to sell new ones is in their office, and for money.
And the question is: with what fright was the block replaced? The intercom was really broken, and they were given a request for repairs?
Or, for prevention, the intercom was "forgotten" the old keys, and they started selling new ones?

Answer 2

If the key standard is the same, they can program it.