How to select alternate addresses for a contact when using the Select Addresses dialog box?
How do you select alternate addresses for a personal contact when using the "Select Addresses" when composing a new message?
Resolving the problem
This is not possible. An Enhancement Request was submitted to Quality Engineering under Software Problem Report (SPR) GMAA8P9MDA.
Workaround for users running Notes 8.5.x Standard:
Use Type Ahead, contacts with multiple addresses will include an arrow next to the type ahead drop down entry, which allows users to select alternate addresses.