$2 LT 1928B to 1928C changeover in 1934

So when the transition from $2 1928B to 1928C occured in 1934 at the B090xxxxxA serial number range it appears like they moved onto the 1928C series and NEVER printed (finished) another 1928B sheet again.  

This is vastly different than what occurred during the 1928A to 1928B transition when both series were intermingled on the press for about a year while going back and forth between 1928A and 1928B notes, with the 1928A notes still being finished until about 9 million into the BA block.  

The transition from 1928C to 1928D also saw this intermingling between series for a long period of time.  

So why did the 1928B abruptly stop with no further mixing of sheets once the 1928C series began?

I'm probably the first one to ever think about this.

1928B was old clause and 1928C was new clause. 

Old clause: This note is legal tender at its face value for all debts, public and private, except of duties, imports, and interest on the public debt.

New clause: This note is legal tender at its face value for all debts, public and private. 

Last $2 1928A / 1928B was numbered April 23, 1934.
First $2 1928C: May 07, 1934

Same gores for the $5

Last 1928 / 1928A: June 16, 1934
First 1928B: June 18, 1934

Adding: All leftover $2 1928A/B stars and 1928 / 1928A stars were destroyed.

Yep that explains it. That's what Jim Hodgson told me too.

Larry - Your inquiry is explained in these two articles.

“New Deal Changes to the Legal Tender Status of Currency.” Paper Money 51, no. 2 (2012, Jan/Feb)
“First Serials on Legal Tender 1928 United States Notes.” Paper Money 54, no. 4 (2015, Jul/Aug)

Great information everyone.

I am fairly new, but am learning a lot.

Larry: Post your other notes if you would.

How many different serial ranges of 1928C stars do you have ?