You can resize the underlying journal volume, but there is a process to do so in the Admin Guide. Typically, users will just increment the number of volumes when growing it. If they are too small and you wanted to redo all of them, I might suggest to just take the hit and swap them out if the CG can tolerate a full sync.  If you do grow them, you want them to all be the same size as they stripe across each other for best performance, so it is generally a good idea to keep them the same size.  As for thin provisioned LUNs, it is generally a best practice to make them thick provisioned since they eventually fill up anyways and it provides predictable performance to the journals (which really counts on the target side for all the I/O processing).  HTH,  -Keith
Hi  I have recently joined an Organisation and had my first exposure to RecoverPoint.  I have been told that we need to increase the Journal Size on the consistency groups as they are way to small.  (we have a consistency group with 25.5 Tb of data using a 200 Gb Journal)  What I am asking is can I expand the single Volume we have in the Journal or do I need to ad more.  If so do they all need to be the same size or can I add say 4 x 500 Gb LUNs and then remove the 200 Gb one.  Also looking at the LUNs on the Storage arrays (VNX5300 & VNX5400) I can see that they are thin provisioned will that have any impact on performance or is it not a concern. 
RecoverPoint Journal Volumes