read closely, it said for the RM149 5Mbps package only 

1) to upgrade that 5Mbps to 10 Mbps - mostly done if not all, so by next yr easily doable
2) to double the speed and decrease price for that particular package in 2 yrs, wait slow slow la

I would be on the side of caution for the below reasons;

1. We don't have any detail yet on TM plan for the 'upgrade'. Is it limited to lower Tier plan 5mbps --> 10mbps only?

2. TM says it will be rolled out in phases. Does this mean it's area dependent?  Is TM infrastructure ready at your area for the upgrade?

but then, for 10mbps at RM159.00 it is not a bad deal anyway.