I remember the original Road MAP being put up. It served a number of functions:

1. SHOW the players the potential that the STS crew were definititely/eventually going to upgrade Pocket Legends to... after release.
2. Give approx. timeline for expecting it: ie make it feel like a reality on it's way.

Problems arose however:

1. Delays
2. New directions eg optimization of all the char models because players demanded GREATER customizations.

Hence, the devs basically DID update PL amazing number of times with loads of quality updates eg

1. Content: Maps/Levels/Mobs/Items etc
2. Modes: PvP modes
3. Features: Better UI/Shop etc
4. Special events and so on....

So I guess after the devs gained our trust *us players* and we knew they'd continue to deliver, they decided that it was less useful to use the roadmap so far in advance and disappoint. So they now update when they feel it's suitable eg 1 Year anniversary etc.

I'd like to see an update for roadmap and have pestered them, but I can see why they have sorta left it but still keep communicating with the players

TL;DR: Roadmap served it's purpose back in the day, now other ways for devs to inform on updates without falling behind on their promises - is my guess