When sending messages to individual phone numbers (e.g. holo send --to 4046661234), the from number is defaulted to the person's campaignContactId. As that value shouldn't be changed, there could be a time where that campaign is finished or should not be sending out messages.

A --from option should be allowed to override this option (either with a passed number or a campaign), and the default should be how duplicate people are handled in holo_sms.send: the most recent linked campaign in CampaignPeople should be used instead.