Alternative anchors in combining?

In some situations, a component might need multiple anchors of the same type. For example, it is common to use such alternative top anchors for Vietnamese diacritics. Alternative anchors share the name of the original anchor but use an underscore suffix for differentiation. So, there might be a top and a top_alt or top_viet anchor on the same glyph layer. The suffix after the underscore can be chosen freely.

Is it possible to make it work the other way, with two anchors in a combining mark and decide which one use in composite glyph?

For example, I would like to have _top and _top.center in my dieresistonos and then be able to choose, in my upsilondieresistonos or iotadieresistonos, which one to link with top anchors.

That is not possible. I tried it a few time and I didn’t get it to work.