the Ordo is not always the complete story

Very true, our EF Diocesan Ordo has been totally confused about the Vigils of Epiphany, Ascension, Pentecost, and Assumption for years.

the original question

Actually, the OP's question was about Mormon music, we seem to have wandered.

AFH, point taken! I'll just answer the tangential question!

Dad, you are quite correct in so far that while the common Masses of our Lady through the year can be used as votive Masses, they are not a defined votive in themselves. In our case the priests requested an indult from the Ordinary to celebrate annually a votive Mass of our Lady as a special, solemn parochial celebration (the Rorate Mass).

General Rubrics of the Roman Missal
Section VI - Votive Masses ## 370-372 and ##309

Votive Masses of the 2nd Class
...
370. The Masses with which this section deals are concerned with special celebrations proper to certain particular groups or to only a part of the faithful.
Special celebrations of this kind are:
a) for parishes: ... extraordinary solemn celebrations, and the like;
...

371. A Mass of this kind, ... is celebrated either by order of the respective ordinary or with his consent.

372. A suitable Mass is chosen to be celebrated on these occasions, according to the different kinds of occasions; for example, ... of the Blessed Virgin Mary, ...

309. The following may be celebrated as votive Mass of the Blessed Virgin Mary:
a) in the universal Church, the Masses assigned in the missal according to the various seasons for the Saturday celebration of the Blessed Virgin, and also all Masses of feasts of the Blessed Virgin Mary which are inscribed in the universal calendar;

So, not a votive Mass on it's own, but a votive Mass with permission from the Ordinary.

:)

A number of people are surprised when we take our break... but I think there are lots of good things that come out of having the summer off.

We always sing August 15th. Season officially ends at end of June. Choir has "mostly off" through the summer - occasional wedding (voluntary); Assumption (mandatory); corresponding practices. The new season starts mid-September (typically 2nd Sunday of September).

In previous parish, we had only low Masses through the summer. Organist, no choir. When some of our girls got scholarships to the organ guild, we used summer as an opportunity for them to plan a music program; 3-4 girls singing by themselves accompanied by one of the scholarship recipients for the low Mass - great opportunity that they lacked through the normal season... with myself or assistant choir director in the loft to assist and make sure they were all set. They had a chance to play much more than at a sung Mass (most things were a cappella); a chance to see more of how things fit in context with an opportunity to get explanations of what to look for in the sung Mass, etc.. Interestingly, there was some burn-out for them by the following Holy Week, even with the reduced schedule in the summer.

In current parish, I sing the Masses through the summer (with a substitute if I take a vacation, not common, but perhaps more likely as I get older). I want my choir members to have a chance to attend Mass with their families for at least part of the year. I push them hard during the season, and I want them to have an opportunity to recharge their batteries physically and spiritually during a break.

I had one or two in the choir who wanted to sing year-round... until they experienced the break. Then they acknowledged how valuable it had been for them.

Perhaps I misunderstood your final point:

[These would be special exercises in honor of the Immaculate Heart of Mary.]

So, although disjointed in these back-and-forth items, the Saturday Votive of BVM is NOT allowed on 3rd class feasts, and the Saturday Votive of IC is, but only if there are exercises--which I daresay may not have actually occurred.

which does not seem to agree with my reference to the rubrics of the Missal. Apologies for my mistake.