1944 SENTA, Rubber canceller

Recently I found a Senta letter cancelled with an unusual canceller. At first glance, the cancellation seemed very strange, but then I found exactly the same cancellation on the special commemorative sheet I obtained from the Senta city archive. It is still not clear why this provisional rubber canceller has been used at the beginning of 1945...

1944 Senta provisional issue, letter, properly franked with 30 f, sent from Senta (2.I.1945) to Mol, cancelled with provisional rubber canceller.

Provisional rubber canceller.
POŠTA  /  ___ ★ 194_  /  SENTA 

Before I show that special commemorative sheet with the same rubber cancellation, you need to know that at the end of October 1944, the National Liberation Committee in Senta issued commemorative sheets with Senta provisional stamps (for more see here).

Senta commemorative sheet

At the end of the 1944 or at the beginning of 1945, after the new DFJ stamps arrived, they made new commemorative sheets in such a way that they simply overlay a piece of paper on top of remained sheets, leaving only the upper inscription with a five-pointed star and the blue/red border. Interestingly, this time they used the same canceller as on the above-mentioned letter.

Modified Commemorative sheet. Note how they overlap original content.
(Click on image to enlarge)

The same provisional rubber canceller.

Update: see also 1944 SENTA, Rubber canceller - 2