You do not have to gt the registration cancelled, it is not binding on you.
Since you have already file a suit for partition you may concentrate on it properly and conduct the case without any lapse from your side.
If you apprehend your siblings to sell or alienate the property in any manner, you may file an application under order 39 rule 1 and 2 seeking injunction restraining the defendants from alienating or encumbering the property in any manner till the disposal of the main suit.
You cannot file the IA for interim injunction at high court.
Even though the courts are on vacation, the vacation court would be functioning, hence you may ask your advocate to file an online emergent petition for interim injunction before the vacation court.