RE: Update coming27 Feb 2020 10:51
First, the share-price drop is in itself a consequence of the mystical arts of AIM's MMs - but if you believe that this market functions seamlessly and perfectly in valuing its listed companies in respect of their true value, then I applaud you.
Second, silence is the answer when no notable news exists to report to the market; the payment was made to NAE, in Jan - that much was clear: if you bothered to look at the payment schedule, published in one of last year's RNSes, then you would have noticed it; however, had it been missed, it would have been reported to the market: it would have constituted a failed obligation. Again, if you read the RNSes, you might be able to discern that money should be available for April's payment.
Third, even though the funding negotiations started, a while ago, the time taken between then and now - and despite being told they were at an advanced stage - would not necessarily equate to an imminent conclusion: such talks inherently comprise many details to delineate, resolve, and finalise; palatable compromises by all parties; and a deal whereby all sides feel they commercially benefit; and, moreover, they are taking place in a geopolitically uncertain climate.
Fourth, previous RNSes declare that NAE exhibit a flexibility to negotiate an extended timeline for payments.