Thank you for providing a sample of what you are transcribing. It helps us in discussing a proper reply but also introducing a topic for discussion that many transcribers may not know about.
We consulted a Braille Formats expert and discussed BF §16.11 Keying Technique for Marginal Labels. The expert confirms that you are following the rules correctly for marginal labels. §16.11.1.g describes a very unusual use for braille grouping indicators.
To answer your original question, based on the UEB rules for “standing alone,” the “it” alphabetic wordsign is not permitted since the grade 1 indicator and the opening braille grouping indicator do not appear on the list of punctuation and indicators that may precede a letter or letters-sequence to be considered as standing alone. [UEB §2.6.2]
Thank you again for your very interesting question. If we can help with any other problem, please don’t hesitate to ask an expert.
Dan Gergen, Chair
UEB Literary Committee