what does EXACTLY mean for a former regiment to be converted to a brigade? What changes?
Need to look for details, but so far each Division had 3 subordinated Regiments. During 2012 the PLAAF issues a reform, that converted a few Divisions to Bases (not entirely sure, but it's an organisational promotion), which have now up to 5 subordinated Brigades instead of Regiments.
This resulted also in a renumbering from the so far common "xx minus 11" system to a new one:
So far - on example of the 33rd Division. their serial is 4xx4x = 44 - 11 = 33rd Div.
The Brigades follow a different pattern and if correct no longer the Regiments will command the number but the former Regiment:, aka here the 98th Regiment will become the 98th Brigade and so the number "should" be 70x9x ... 709 - 611 = 98 !
Deino