Bedrock Edition:Info update
info_update and info_update2 are placeholder blocks.
Obtaining
Info_update blocks have never been intended to be obtainable, so normally the only way to obtain these blocks is with a NBT Editor.
Pre-v0.2.0 wool
Before v0.2.0 alpha, all the different colors of wool were split up into their own numeric IDs since the player's inventory did not support metadata values at the time. With the addition of inventory metadata support in v0.2.0, all wool colors were merged into a single numeric ID, with different colors corresponding to different metadata values. If the player updates to v0.2.0 only, any pre-v0.2.0 wool blocks are automatically converted to the new wool ID. The game's ability to convert wool was removed in v0.2.1, resulting in most wool colors getting converted to info_update2 blocks if the player updates from v0.1.3 or earlier to v0.2.1 or later.
Falling block transmutation
Both info_update and info_update2 are obtainable via falling block transmutation from beta 1.16.0.52 to beta 1.16.100.52.