Tier 2 dependents extension - SOC change to shortage occupation

[eissaa]

First thanks for everyone helping on this board, has been very helpful so far.

My wife and son's visas expire 14/06/2020 and I am starting the application.
I hold a 3 year Tier 2 (General) visa which is due to expire 9/2022.
After my application, my SOC has been included in the shortage occupation list.

my question was about applying as a shortage occupation when applying for my wife and son's visa extension or should I apply as per my original application as a (Tier 2 General)?

Many thanks for your help.