FTSE Russell released the changes to the STI Index following its quarterly review earlier today. Similar to the predictions of the MSCI Index changes, we were spot on again with Mapletree Industrial Trust being added and SPH being deleted. In addition to the index rebalancing, the new reserve list, by market cap, is as follows, FLCT replaces MNACT:

STI Index Inclusions & Exclusions (Source: FTSE Russell)
As explained in the first post about the STI Index rebalancing, the criteria and method of calculation for the index is publicly available from the index provider (FTSE Russell) so it is not difficult for any layman to do such calculations beforehand; it just takes some time to do so.
After this announcement, investors should take note that the changes will be applied at the close of business on 19 Jun and will be effective on 22 Jun. While the STI Index is less traded