Space:

I cannot find �A Rule� such as you describe.

�By the time I HAD DONE my shopping and (HAD) CLEANED the house, Saturday WAS nearly over�.� PAST PERFECT TENSE & PAST PERFECT TENSE & PAST SIMPLE TENSE

(�Saturday was nearly over by the time I had done my shopping and cleaned the house�.)�

�Usually, by the time I DO my shopping and CLEAN the house, Saturday IS nearly over�.� PRESENT SIMPLE TENSE & PRESENT SIMPLE TENSE & PRESENT SIMPLE TENSE

�Usually, by the time I HAVE DONE my shopping and HAVE CLEANED the house, Saturday IS nearly over�.� PRESENT PERFECT TENSE & PRESENT PERFECT TENSE & PRESENT SIMPLE TENSE

�Last week, by the time I DID my shopping and CLEANED the house, Saturday WAS nearly over�.� PAST SIMPLE TENSE & PAST SIMPLE TENSE & PAST SIMPLE TENSE

�Last week, by the time I HAD DONE my shopping and HAD CLEANED the house, Saturday WAS nearly over�.� PAST PERFECT TENSE & PAST PERFECT TENSE & PAST SIMPLE TENSE

�Next week, by the time I DO my shopping and CLEAN the house, Saturday WILL BE nearly over�.� PRESENT SIMPLE TENSE & PRESENT SIMPLE TENSE & FUTURE SIMPLE TENSE

�Next week, by the time I DO my shopping and CLEAN the house, Saturday WILL HAVE BEEN nearly over�.� PRESENT SIMPLE TENSE & PRESENT SIMPLE TENSE & FUTURE PERFECT TENSE

I believe that these sentences are grammatically correct and are perfectly acceptable. There are probably others.

I hope that this helps you.

Les Douglas