Thanks, Leonid!
About "шисбр" I've just thought the same... I'm not sure but AFAIR in such brigades there were flame-thrower tanks, sometimes mine-clearing tanks, and other heavy stuff for destroying fortifications.
About 30th BAD: for me this could mean something like that: as the 6th Gds Mortar Div (Katyusha) fought with 2nd UF since Yassy till the end of war, and in April 1945 is mentioned as having only 2 brigades (8th Guards and 33rd), and 30 BAD came to Hungary in September, the 37th Gds rocket brigade could be moved from 6th rocket div to 30 BAD; or the 6th rocket div had only two brigades, with 30th BAD having its own rocket brigade.
Anyway, quite terrible force...
Dear gentlemen Hannes, Rafik, Evgeniy & Oleg: thanks to Your help, as well to Leonid's, I finally managed to collect the OoB for red Army's 2nd & 3rd Ukrainian Fronts for Balaton Battle and beginning of the Vienna operations. If Leonid is the same Leonid I know, (and I presume he is...) I send him the *.doc file with that OoB. If someone of you is interested in that file, please let me know - so I could send it to him as my thanks.
Thank you!
DS