I stumbled upon your question whiile searching for Globe's new FUP before upgrading my 5Mbps with 10GB per day data cap to a much more higher speed but then I found out that this 256Kbps is a thing now and this speed is listed on every DSL and Fiber plans to have 256Kbps speed "upon full consumption of data allowance". It was highlighted in yellow.
"Minimum guaranteed speeds: 30% of subscribed speed (for Fiber); 256kbps (for DSL/ LTE). 256kbps speed applies upon full consumption of data allowance."
I guess I won't be upgrading anytime soon, only until Fiber plans with more than 300GB monthly datacap will be available in our area.