In our environment, CTS+ is configured on solution manager production system.
So transport numbers are used from SMP table E070L and configured java landscape systems are also listed in this table.
1. Find last java transport and note down it's number.
2. Find where your CTS+ is configured and login to that system
3. goto table E070L, look for your java development system and number you find in step1 should match here.
4. You need developer access to change this number.
I hope this will help.