Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
Availability is regular. It follows the -ies Conversion rule.
Use plural verbs: "The availabilities are ready" (not "is ready").
Yes. The plural availabilities is standard across all English variants.
The word availability follows the standard English pluralization rule. When forming the plural, availability becomes availabilities. This follows the -ies Conversion pattern, which is one of the most common plural rules in English.
Understanding why availability becomes availabilities helps with spelling and pronunciation. Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
When using availabilities in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The availabilities are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.