Yes unacceptable but caused in part by the unacceptable actions of some pilots in the past breaking their side of the bargin and leaving: without the agreed notice period, not paying their bond off or causing disruption. How did you expect the companies to respond? Childish but this is the only way they can punish. On the whole the pilots work force started this. If you leave on a good note complying with your agreed obligiations this will not happen. I agree the tone of the email (if true) is awful but it may be slighly changed in translation by the reporter.