Alarm duration with an unprogrammed Key

[Nickcarey]

Hi,

Mrs Managed to lose the only key for 2015 polo, so had one cut by local VW garage (ouch £170) and now need to get it towed over to them for it to be programmed.
Thought I will try the key and got in the car and as explained to me the alarm did go off. It eventually turned off but it felt like it took ages as I faffed around with trying to turn the ignition on\off. I was told the alarm will go off for after a couple of seconds and as soon as I put the key in ignition it will turn off but it felt like an eternity.
Is there a procedure to this? It’s a Automatic car not that this should matter.
Getting it towed on early next week to the garage but just wondering.

Thanks
Nick