An insurer may deposit cash or government securities eligible for deposit under § 5-701(b) of this subtitle in an amount greater than any deposit required or allowed under this article. All or part of an excess deposit may be released to a solvent insurer on its request as provided in § 5-708(a)(2) of this subtitle. An excess deposit may be released to an insolvent insurer only as provided in § 5-708(a)(3) of this subtitle.